FIG. 1 shows a conventional hand brake disclosed in U.S. Pat. No. 5,865,065 for mounting on a handlebar grip 11 of a wheeled walker to control a cable 5 which has one end connected to the hand brake and the other end connected to a brake structure mounted on a wheel (not shown) of the walker.
As illustrated, the conventional hand brake includes a main frame 2 mounted fixedly on the handlebar grip 11 of the walker to define a working space 23 below the handlebar grip 11, and a control lever 3 having a pivot part 301 extending into the working space 23 to connect pivotally with the main frame 2 about a first pivot 25, and an operating part 302 extending outwardly from the working space 23. A brake member 6 is disposed within an accommodating space 34 of the pivot part 301 and is pivotally connected thereto about a second pivot 36 parallel to the first pivot 25. The brake member 6 is connected to the one end of the cable 5 under tension such that the lower end 63 thereof abuts against a bottom wall 34a of the accommodating space 34 when the control lever 3 is in a non-braking state, as best shown in FIG. 1.
The operating part 302 of the control lever 3 is operable toward the handlebar grip 11 to move from the non-braking state of FIG. 1 to a braking state shown in FIG. 2, where the brake member 6 moves together with the pivot part 301 in order to apply a pulling force to the cable 5.
The operating part 302 of the control lever 3 is further operable away from the handlebar grip 11 to pivot about the first pivot 25 and move from the non-braking state to a parking state, as best shown in FIG. 3, which action in turn, results in upward movement of the brake member 6 such that an inwardly projecting plate 28 of the main frame 2 engages a transverse recess 64 of the brake member 6.
Some of the disadvantages that result from the use of the aforesaid conventional hand brake are as follows:
(a) At the parking state, the brake member 6 is retained by the projecting plate 28 such that when moving the same to the non-braking state, the control lever 3 sometimes has to be pivoted repeatedly about the first pivot 25 in order to disengage the projecting plate 28 from the recess 64 of the brake member 6.
(b) The control lever 3 has to be turned by a relatively wide angle relative to the handlebar grip 11 for disengaging the projecting plate 28 from the brake member 6.
(c) The projecting plate 28 may experience resilient fatigue after long term use, thereby eventually failing to provide firm engagement with the brake member 6.